Unstable angina. Rational approach to management

Area of Science:

• Cardiology
• Internal Medicine

Background:

• Unstable angina is characterized by chest pain at rest with reversible S-T segment changes.
• Decreased coronary sinus oxygen saturation precedes left ventricular dysfunction and chest pain in rest angina.
• This suggests reduced oxygen supply, not increased demand, triggers angina at rest.

Purpose of the Study:

• To investigate the underlying cause of rest angina.
• To propose a treatment strategy for unstable angina focusing on improving oxygen supply.

Main Methods:

• Observational study in cardiac catheterization laboratory.
• Stepwise treatment approach for patients in Coronary Care Unit.
• Administration of intravenous nitroglycerin, beta-blockers, and calcium channel blockers.
• Consideration of intra-aortic balloon counterpulsation and coronary angiography.

Main Results:

• Reduced coronary sinus oxygen saturation was identified as the primary cause of rest angina.
• A stepwise treatment protocol was proposed, starting with intravenous nitroglycerin.
• The protocol includes titration of beta-blockers and calcium channel blockers, with advanced therapies for refractory cases.

Conclusions:

• Treatment for rest angina should prioritize enhancing myocardial oxygen supply.
• A stepwise approach involving vasodilators and other anti-anginal agents is effective.
• Advanced interventions like angioplasty or bypass surgery are options for suitable patients.